Both clubs have made stuttering starts to the new Premier League season to leave them some way off pace-setters Liverpool FC after just four games.
Chelsea FC have only won one of their opening four games to leave them with five points and already seven points off top spot.
Manchester United, too, have only picked up one victory so far this term following their 4-0 beating of Chelsea FC at Old Trafford on the opening weekend of the season.
Wenger’s former club Arsenal, meanwhile, are two points ahead of Chelsea FC and Manchester United but they are still five points behind the leaders.
And Wenger has now delivered his assessment on both Chelsea FC and Manchester United’s starts to the new campaign.
Speaking in an interview quoted by Metro, Wenger said: “Maybe the team who has the potential is Arsenal who could be the closest [to the title challengers].
“Chelsea looks a bit young, not enough maturity up front and not enough maturity at the back
“Man United hasn’t found a settled way where you could say today they could fight for the championship.
“They look quite comfortable, the two in front, they know they can do it.
“Man City has a huge technical level where they can always create chances.
“Liverpool looks very strong at the back and up front they have a midfield that knows its job. Maybe less creative than Man City but they look a little bit in front of the all the others.”
Chelsea FC will return to Premier League action after the international break when they take on Wolves away from home on Saturday.
Manchester United, meanwhile, are gearing up for a home clash against Leicester City at Old Trafford this weekend.
Arsenal will travel to Watford on Sunday 15 September.
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